<html lang="en">
<head>
    <meta charset="utf-8">
<title>JavaScript</title>
<style>
h1{
    background-color: rgb(243, 162, 0);
    margin: auto;
    margin-top: 200px;
    width: 600px;
    height: 400px;
    line-height: 400px;
    text-align: center;
}
</style>
</head>
<body>
</body>
<script>
for(var i=0;i<1;i++){
    document.write("<h1>hello world  dgdhrtjs </h1>");
}
</script>
</html>